For years people have justified manned space exploration in the name of science: we need to collect data, conduct experiments, gain scientific insights.
But many scientists agree that such justifications aren't exactly fair. Most scientific needs can be met by sending unmanned probes into space. In fact, such probes are generally better for science because they cost less, they have more room for scientific instruments, and they don't have any of the constraints required to keep humans safe on a manned mission. An unmanned probe doesn't need air, water, and food; it can even get lost never to return. A manned spaceship can't.
So, if spending billions of dollars on a manned mission to Mars isn't exactly good for science, and if saying that we're doing it in the name of science isn't exactly an effective way to rally public support, what are some good reasons for mounting such a mission?
Some people say that the only good reason is simple and fundamentally human: we should go because it's there. Space, and Mars in particular, have always captured our imaginations. So when we go to Mars it will be for the thrill of it, for the pure wonder, adventure, and excitement of pushing beyond familiar space territory toward a new frontier and seeing for ourselves what is there.
